RGB
Also known as: red, green and blue
The abbreviation for the color model RGB stands for Red, Green and Blue. It is a system for capturing colors in a code. Colors are derived in the RGB system in shares of red, green and blue.
RGB is a so-called additive color model. In this, black is the base color, with color components used to add certain colors of light. By displaying all the colors together, white can be obtained. This makes RGB different from subtractive color models such as CMYK, where mixing all colors together actually produces black.
RGB color coding is primarily used for colors displayed on a monitor. In addition to computers, tablets and smartphones, televisions have been using the RGB color system for decades. The degree of red, green and blue light collectively forms the desired color. For example, by mixing red and green, yellow is obtained.
Number of RGB colors and notation
Usually, RGB colors use 8 bits, so that the proportion of each mixed color can be expressed in 255 steps. Thus, 16.7 million different colors can be encoded.
RGB colors are notated in both the decimal and heximal systems. The following example notations are color codes for the same color purple: #8b44c0 and rgb(139, 68, 192). The first (hexadecimal) notation is widely used in web design.
In RGBA, an extension to RGB, an alpha value for transparency can be specified in addition to the color values for red, green and blue.